The ABCs of English & Metric Pin Gages
Plug Gage Measuring
The art of using pre-sized precision metal plugs to determine the acceptability of diameters of drilled or machined holes. The difference between any class of gage is not the wear or life span of the gage, it’s the tolerance which is allowed in the manufacturing process of the gage.
A GO gage is used to check the lower limit of a hole. A NOGO gage is used to check the upper limit of a hole. If the GO gage enters the hole and the NOGO gage is unable to enter, the design specifications of the hole have been met.
Uses – for precision GO/NOGO measuring of hole sizes and depths, checking hole location and distance, and setting micrometers. All gages are uniformly 2″ long with ground ends, allowing you to use both ends for increased gage life. Gages are Carbon Chrome Alloy Steel (grade 52100 bearing quality steel) and heat treated to a 60-62 Rockwell C hardness. All of our products come with a Certificate of Class Conformance, traceable to NIST (National Institute for Standards Technology). The size and “+” (GO) or “-” (NOGO) are laser etched with a Meyer Exclusive Serial Number feature to ensure traceability on your shop floor on all gages that are .061″ and larger.
These pin gages have an inch tolerance of .0002″ and a metric tolerance of .005mm. They are practical where good precision and speed are important. (Note diameters above .8250″ or 20.96mm tolerance increases, see gage makers tolerance chart)
These class z gages have an inch tolerance of .0001″ and a metric tolerance of .0025mm. They are one half the deviation of the ZZ for a better fit. (Note diameters above .8250″ or 20.96mm tolerance increases, see gage makers tolerance chart)
These gages are available with an inch tolerance of .00004″ and a metric tolerance of .001mm. These gages are used where greater precision is needed. (Note diameters above .8250″ or 20.96mm tolerance increases, see gage makers tolerance chart)
These gages have an inch tolerance of .00002″ and a metric tolerance of .0005mm. They are one half of the deviation of the X. Great for your most critical needs. (Note diameters above .8250″ or 20.96mm tolerance increases, see gage makers tolerance chart)
All our gages are 2 inches or 51mm long with ground ends for long life.
This is bearing quality, Carbon Chrome Alloy Steel, heat treated to 60-62 Rockwell C hardness and is considered the preferred material for the highest quality plug gages.
Certificate of Class Conformance
Assurance issued with each shipment of quality gages that conformance characteristics are traceable to NIST.
National Institute of Standards and Technology
Serial Number Etching
A feature that is exclusive to Meyer Gages and essential in assuring traceability on the shop floor on all gages over .060″.
Gage Makers Tolerance Chart
Plain Plug, Plain Ring & Master Gage Tolerances
|.0009″ to .8250″||.000020″||.000040″||.000070″||.000100″||.000200″|
|.8251″ to 1.5100″||.000030″||.000060″||.000090″||.000120″||.000240″|
|1.5101″ to 2.5100″||.000040″||.000080″||.000120″||.000160″||.000320″|
|2.5101″ to 4.5100″||.000050″||.000100″||.000150″||.000200″||.000400″|
|4.5101″ to 6.5100″||.000065″||.000130″||.000190″||.000250″||.000500″|
|6.5101″ to 9.0100||.000080″||.000160″||.000240″||.000320″||.000640″|
|9.0101″ to 12.2600″||.000100″||.000200″||.000300″||.000400″||.000800″|
|1.00mm to 21.00mm||.0005mm||.0010mm||.0018mm||.0025mm||.0050mm|
|21.01mm to 38.00mm||.0008mm||.0015mm||.0023mm||.0030mm||.0060mm|
|38.01mm to 64.00mm||.0010mm||.0020mm||.0030mm||.0040mm||.0080mm|
|64.01mm to 115.00mm||.0013mm||.0025mm||.0038mm||.0050mm||.0100mm|
|115.01mm to 165.00mm||.0017mm||.0033mm||.0048mm||.0060mm||.0130mm|
|165.01mm to 230.00mm||.0020mm||.0041mm||.0061mm||.0080mm||.0160mm|
|230.01mm to 300.00mm||.0025mm||.0051mm||.0076mm||.0100mm||.0200mm|